I've had brushes with only 3 famous (maybe semi-famous in some cases) people.
First up (on two separate occasions)
(That's the greatest action hero in the world standing next to Jackie Chan!)
I also met Ken Lo, action star of many Hong Kong movies (kinda unknown in the US)
I also met Colonel Lee Joseph Archambault, the pilot of the space shuttle Atlantis!
I'd almost list singer Willie Nelson here, but I don't really count it because I didn't know it was him until someone asked me if I'd noticed Willie Nelson walking past me.